The professor and his daughter

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Professor Stephen Hawking and his daughter Lucy Hawking give a lecture entitled 'Why We Should Go Into Space' during the 50 Years of NASA lecture series at George Washington University in Washington, DC, April 21, 2008.

Professor Stephen Hawking and his daughter Lucy Hawking give a lecture entitled 'Why We Should Go Into Space' during the 50 Years of NASA lecture series at George Washington University in Washington, DC, April 21, 2008. (Getty Images)

Professor Stephen Hawking and his daughter Lucy Hawking give a lecture entitled 'Why We Should Go Into Space' during the 50 Years of NASA lecture series at George Washington University in Washington, DC, April 21, 2008.